1. Field of the Invention
This invention relates generally to a trolling motor which includes a propeller, motor housing, and support column cleaning function. More specifically, it relates to a trolling motor which includes a motor control system which is capable of executing a predetermined sequence of events which will loosen or clear entangled weeds from the propeller, motor housing, and support column.
2. Background
Trolling motors are waterproof electric motors, typically under two horsepower which are fitted with a propeller and used to control the movement and position of fishing boats. Operation of trolling motors in weed infested waters has long been recognized as a problem. Weeds become entangled on the support column, the motor housing and the propeller, thereby causing a dramatic reduction in performance, even to the point where propulsion of the boat becomes impossible. Typically when weed fouling occurs, the user first attempts to remove the weeds by manipulating the controls of the trolling motor. This might involve increasing the speed to full speed and steering the trolling motor in a different direction. When this method fails, the user must pull the trolling motor out of the water and remove the weeds by hand. This, however, is not a satisfactory situation since during the time the trolling motor is out of the water, the boat is free to drift, often times moving further into weed infested areas and making the situation worse. Furthermore, if the trolling motor is not equipped with an automatic shut-off which operates to disable the motor when it is out of the water, hand cleaning could present a potential safety problem. Over time, numerous techniques have been developed to deal with weed entanglement but none of these techniques has proven satisfactory for all operating environments.
For example, devices have been developed which attach to the motor housing and support column which are intended to deflect weeds away from the propeller. Unfortunately, these devices create drag which hampers the effectiveness of the trolling motor even when not in weed infested areas, they provide no protection for the support column or motor housing, and they do not completely eliminate entanglement of the propeller. In fact, these devices themselves can collect weeds, thereby adding additional drag and making the trolling motor difficult, or impossible, to steer.
A second approach has been to utilize specially designed propellers, commonly called weedless propellers. These propellers are shaped such that they reduce weed gathering and shed, rather than collect, weeds. However, the performance of these propellers, in regards to their ability to self clean, changes with propeller speed. Fouling of the propeller, support column, and motor housing is much more likely to occur at low speed operation than at high speed. Additionally, these propellers do not reduce weed fouling of the support column and motor housing, which causes further drag and reduces the effectiveness of the trolling motor.
It has been recognized that momentarily reversing the direction of rotation of the motor can cause entangled weeds to disengage from the propeller. However, most trolling motors which utilize a foot pedal control do not provide any means for reversing the motor. Even with trolling motors which have a means for reversing rotation, the user must manually activate reversal of the motor, thereby disturbing the present speed setting, and thereafter must manually reset the motor to the previous forward speed.
It is thus an object of the present invention to provide a reliable means for cleaning weeds from the propeller, support column, and motor housing of a trolling motor without adversely affecting the operation of the trolling motor.
It is a further object of this invention to provide the trolling motor operator with a means for manually activating a cleaning cycle or periodically activating cleaning cycles without disturbing the preselected forward speed setting of the trolling motor.
It is still a further object of this invention to provide detection of weed fouling of submerged elements of the trolling motor and to automatically activate a cleaning cycle when appropriate.